Grounding clamp



May 19, 1931. H. K. CALDWELL 1,805,804

GROUNDING CLAMP Filed May '7. 1929 BY @www ATTORNEY Patented May 19, 1931 N HENDRIX K. CALDWELLJOF SAN DIEGO, CALIFORNIA 7 y GROUND:

i Aiypnetion filed May 7.'

invention relatesto grounding clamps, y

'y tively, at each of their corners.' These lugs,

andthe vobjects of my invention. are :y first, to provide a grounding clamp vwhereby .la Vpositive andV lasting connection between the ground wireof an electric circuit and a waterpipe, gaspipe or other grounded' pipe, 1s en sured; second, to provide a ground clamp which grounds the wire conduit as well as the ground wire; third, to provide ka grounding 10 device which is easy toinstallvwithou't the aid of special tools; fourth, togprovlde a grounding device which has'a minimum number of parts; fifth, to provide a groundingv device which is rigid and sturdy of construction, and sixth, to provide a grounding clamp which is simple of construction,

durable, efficient in its action, and which'will not readily deteriorate or get out of order. With these and other objectsin viev;TA as' will .appear hereinafter, my invention consists of certain novel featuresofconstruction, combination and arrangement vof parts `and portions as will behereinafter'described in detail and p'articularlyjset fforth in the apf pended claims, referencebeing had .to the ac-l companying drawings and tothe characters of reference thereon which form a part yof this application, in which: n i Figure l is a top or plan View of my grounding device; Fig.V 2 is a sectional view thereofthrough 2-2 of Fig. li'withlthe grounded wire shown inv elevation;l Fig. 3 is` an end lelevationalview thereof` with the Ulower clamp segment and Wedging cap .ref

moved; and Fig. 4 is a perspective view ofv theclampingplug.. .n .n ,A y

Similar characters of reference. referto a similar parts and portionsthroughout the `,several viewsA of thedrawings.

40 Clamp 'jaws l and 2, screws 3, nipple 4,

wire Vclamping Vplug 5, wedging cap 6, yconstitute the principal partsY and portionsv of my grounding clamp.

v Two clamping jaws l and 2 are provided each of which is semi-circular in cross section. These clamping jaws are adapted to extend along a grounded pipevG, such as a a waterpipe or gaspipe a suliioient distance for forming a satisfactory contact therewith.

The clamping aws l and 2 are provided with NG cLAM-r `1929. seriai'n. 361,239. l

oppositely disposed lugs la and 2a, respecyare provided with valined holesiorreceivng screws 3, each of which is adapted to receive4 a Washer 3a and a nut 3b so that said screws may rigidly secure saidpclamp jaws .around the grounded pipeGr.y 'j y A nipple 4 is integrally connected ,thro'ughly a neck portion 4a with the upper clamp jaw gi i 2, as shown best-,in Figs.Vv 2-,and-3 ofthe draw-y ings. The'nipple 4 is provided with a boreilb; l f

therethrough which extends substantiallyat- Vright angles Aand transversely tothe ,axisofxthe ground clamp jaws 1 and2'. .Tghe vone Vend portion 4c of this bore l4Z) isV internally;

threaded for receiving theend of'an electric.

The otherend of the nippley 4 isreduced in" 4d has an.outer.diametersimilar A.to thefin'- v.n er diameterof the internally threaded piortion 40' so that a conventional conduit capi. l

y member adapted to be normally screwe'don the end of a conduitl C may he screwed onto the threadedportion'4cl; The portion of .the lbore 4b extending within. the externallyr threadedy portion 4d is tapered so that ,thev walls thereof diverge towards the extended end of saidl externally threadedk portionl 4d' "forming a wedging 'surface 4e.v

A wire clamping plug. Y5 is provided with; a tapered portionfa corresponding to the Y ltaperedportion`4e so that said plugtends to,A f a 851?-l wedge whenforced inthe wedge portion 41e towards the conduitC. The plug A5 is propk vided with aslit 5b which ybifurcates the plug except for a small'narrow web c'locatedv at i the inner or smaller viend andto one sideof said plug, as shown best in 'Fiig.2.l yThe plug 5 is provided witha centen'.v longitudi'nally'v y extendingl bore 5d which is intersected longitudinally by the' slit 5b. n The bore 5d has a flared portion eat the inner or smaller end of the plug, as shown best in Figs. 2 y,and 4.

A wedging cap 6 is adaptedto screwon.

the externalthreads 4d and force the plug 5 into the Vwedging portion V4e of the nipple '4.. 'lhe insulation I fromthe grounding wire'W'` is removed from the end thereof and the wire y W inserted into the longitudinally extending bore 5d of the Wire clamping plug 5, the iared portion 5e of said bore facilitating the insertion of the Wire therein. The bore 5d before the plug is wedged, forms a snug but easily sliding lit with the Wire WV so that the plug may be placed on the end of the Wire Without` the aid of tools. The plug is then inserted' in the Wedge portion 4e of the nipple andthe cap 6 is screwed down until the closedendfa thereof bears against,- the extendedj end; of the plug 5 forcing said plug into the Wedge and constrieting the bore 5d by reasonofithe slit 5b, thereby rigidly and securely clamping:

the Wire W.

Itis preferred that the plug -be made.A outl of -copper, or bronzeor similar material ,which islelativelysoft and will tend to forma 'good Contact with thenvedge portion le andztopw 29 por tion 6aofthe cap. The cap 6. may-,be a,

` conventional conduit Ipipe capbnt itmay be.

provided Witha slight'recess, 6b, in its closed enda sothat the Wire W7 may protrude slightly flOm the plug,- thus thewire. although no tlcut perfectlyfflush with the endpofthev plug; l5f Willv'not interfere with the action of,

the capl 6.

tieular construction, combination andaraq, rangementof parts: and portional dolfnot wishftofbe, limited to` this particularconstruc-v tion, combination'and arrangement, but desireA to Iinicludein the vscope of f my. invention ,the construction, combination and arrangement1A 35, substantially i as Y setiforth. in. the appended claims.

Having-` thus described myinvention, what I claimias new and desireto secure by Letters:

Patent is:

40y yl. In; a; device" of the from said conduit forming awedgingsur; fare, a plugmeans adapted to. clamp a. Wire extending through said Conduit and intosaid bore, and means for `Wedging,saidsplilig into said bore. .s p

2: In@ `device ofthe class deSCribed, amp

ple member, means vfor grounding said nipple member, said-.nipple member provided with a. bore therethrough, aninternally threaded :A portion.I at the onez end of. said nipplev forY re-..

ceiving: the end "of a wire.y conduit, a Ltapered plug having longitudinal` slits, said: slits. ad ted` to receive anvire extendingfrom- Though I haveshfown and described a par@ extending transversely to the pipe clamp, an

internally threaded portion at the one end of said bore adapted to receive the end of a Wire conduit, a tapered plug having an opening extending therethrough adapted to receive a Wire extending from said conduit, said plug bifurcated along said opening except for a--smallrlinlring portion, and means for Wedging said plug into the bore of said nipple so vas to'clamp said Wire and form a positive electrical:connection between said wire and said nipple.

' t.' Ina device of the class described, a nipple integral with a member of a pipe clamp, said nipple provided with a bore therethrough extending` transversely to the; pipe clamp, an internallyY threaded portion atgtlie one end of-"saidi bore. adapted ,to Jreceivef the endyofawire conduit, a tapered'portion at theother end of saidjbore,;a ,plug tapered Ito i correspond to the,lta pere,d' portionof said.;V boresa'id l plug providedl with; an opening', therethrough Ifor receiving, a wire, extending'Y fromfsai d Wire, conduit, said pluglbifurcated, longitudinally rwith said openingv except -`for a smalllinking portion, andmeans for Wedge ing' Seid Plus-info, ,theeperedp0rt0-n 0f Said boreso lasto f orina positive- Contact between said Wire` and saidlnipple; v

5,., In a device ofthe classl described, ,al nip; plev integral Witha member of apipe clamp, said nipple provided ,With agbore, therethrough extendingtransversely tothe pipe clamp an v internally vthreaded .portion atthe one end of said bore adaptedto receivetheA end yof a Wire conduit, katapered ,portion atthe othernend of said bore, a .plug tapered Y to:Y correspond to theV tapered yportion olf, saidbore, said plug', provided with openingV 'therethrough`y for y receiving a Wire lextending,y from` said Wire 'conduit said plug'l 'bifurcate'dj longitudinally with said opening exceptforasmalllinking. portion, said nipple provided vvith'an ,exten-. nally threaded portion surroundiiigI the taperedend of `said bore therethrough, and ,a cap means sereivabl-y mounted VYupon l,said ex; ternal threads, "sa-,id` cap means ,adaptefdfv to bear, against the one end ofsaid'fplugand Wedgev said plugY into the taper-ed portion of, said bore, and canse said @plug tofclamp said: Wire and form a positive Contact there'vvith.

lIn testimonywhereof, I have hereunto set myfhand at' SanijD'ieD'@ California this 17th,

day ofApril, 192,9-

- HENDRiX.IQCALDWELL.,

sai fconduit into, said nipple, meanswfor 60,- wedgingzsaid plug intothe bore of said nip-A ple whereby, said Wire .sfelamped NWithin said slit..`

ple rintegral Withamember of apipe. clamp.,

3, -In adeviceoftheLclassdescribed, afnipe. 

